Adhesive articles with improved air egress

ABSTRACT

This invention relates to an adhesive article which provides air egress. Air egress is provided by supplying a route, such as areas of no initial adhesion for the air to flow out from under the construction. The invention relates to an adhesive article comprising a facestock having a front surface and a back surface, a continuous layer of adhesive having an upper surface and a lower surface wherein the upper surface of the adhesive layer is adhered to the back surface of the facestock, and a plurality of spaced-apart non-adhesive material which is in contact with the lower surface of the adhesive layer. These articles have usefulness as industrial graphics images, as well as decorative coverings, etc. The articles provide air egress and optionally repositionability and slideability.

[0001] This application is a divisional of U.S. patent application Ser.No. 09/742,654 filed on Dec. 21, 2000, which is hereby incorporatedherein by reference in its entirety and which claims the priority ofProvisional Application No. 60/199,244 filed Apr. 24, 2000.

TECHNICAL FIELD OF THE INVENTION

[0002] This invention relates to adhesive articles and methods of makingthe same. The adhesive articles may be used for graphic images, such asthose used on vehicles.

BACKGROUND OF THE INVENTION

[0003] Pressure sensitive adhesives have enjoyed great acceptance fortheir convenience of use. The pressure sensitive adhesive is often usedfor tapes and articles containing graphic images. The advantages of thepressure sensitive adhesives are their strong bonding and simplicity ofapplication. One drawback of these products is the initial tenacity ofthe pressure sensitive adhesive. The positioning of the product must beprecise because of the initial strong bond of the adhesive. A needexists to make products using pressure sensitive adhesives which arerepositionable, i.e. the product may be removed after light applicationof pressure without destroying the product or the substrate. Anotherneed exists for the products to be able to slide. Slideability allowsfor correction of alignment of the product without the need ofcompletely removing the product and possibly destroying the adhesivearticle or substrate.

[0004] When the product is a graphic image and is applied over an arealike a wall or truck panel, there is the possibility of trapping airunder the product and forming bubbles or wrinkles. The product mustexhibit air egress, i.e. the ability of the product to provide a routefor air trapped under the product to be removed.

[0005] A need exists for products which have one or more of thedesirable properties of air egress, repositionability and slideability.

SUMMARY OF THE INVENTION

[0006] This invention relates to an adhesive article which provides airegress. Air egress is provided by supplying at least one route, such asareas of no initial adhesion for the air to flow out from under theconstruction. The invention relates to an adhesive article comprising afacestock having a front surface and a back surface, a continuous layerof adhesive having an upper surface and a lower surface, wherein theupper surface of the adhesive layer is adhered to the back surface ofthe facestock, and a pattern of non-adhesive material forms that are inembedded into the lower or upper surface of the adhesive layer. Theinvention further relates to methods of preparing the adhesive articles.These articles have usefulness as industrial graphics images, as well asdecorative coverings, etc. The articles provide one or more of airegress, repositionability and slideability.

[0007] The method of making the adhesive articles of the presentinvention includes the steps of: (a) applying a pattern of anon-adhesive material onto an adhesive layer that has been coated onto afacestock; (b) embedding the non-adhesive material into the adhesivelayer; and optionally, (c) applying a release liner to the adhesivelayer. The embedding and applying steps may be combined.

[0008] Another embodiment of the method of making the adhesive articlesof the present invention includes the steps of: (a) applying a patternof a non-adhesive material onto an adhesive layer that has been coatedonto a release liner; (b) embedding the non-adhesive material into theadhesive layer; and (c) applying a facestock or a second release layerto the adhesive layer. The embedding and applying steps may be combined.

DESCRIPTION OF THE DRAWINGS

[0009]FIGS. 1a and 1 b are cross sectional areas of an adhesive articlewith non-adhesive material embedded in the adhesive.

[0010]FIGS. 2a and 2 b are cross sectional areas of an adhesive articlewith non-adhesive material embedded and with a textured finish, such asa matte finish.

[0011]FIG. 3a, b and c are cross sectional areas of an adhesive articlewith a non-adhesive material embedded in the adhesive layer at theinterface between the adhesive and the facestock.

[0012]FIGS. 4a and 4 b are cross sectional areas of an adhesive articlewith non-adhesive material in channels within the adhesive layer.

[0013]FIGS. 5a and 5 b are cross sectional areas of an adhesive articlewith a porous non-adhesive material embedded in the adhesive layer atthe interface between the adhesive and the release liner.

[0014]FIG. 6a, b and c are cross sectional areas of an adhesive articlewith a porous non-adhesive material embedded in the adhesive layer atthe interface between the adhesive and the facestock.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] As described above, the present invention relates to adhesivearticles such as those used for industrial graphics. The adhesivearticles provide one or more of air egress, repositionability andslideability for easy application to a substrate.

[0016] The adhesive articles comprise a facestock, a continuous adhesivelayer, and a non-adhesive material. The adhesive article may furthercomprise a release liner releasably adhered to the adhesive layer. Inone embodiment, the non-adhesive material includes non-adhesivepolymers, including ink compositions applied by printing methods. Inanother embodiment, the non-adhesive material is applied by vacuummetallization or by sputtering. The non-adhesive material, after drying,cooling, and/or curing, adheres to the upper or lower surface of theadhesive layer. In one embodiment, the non-adhesive composition containsgreater than 50%, or greater than 75%, or greater than 85% solids. Inanother embodiment, the non-adhesive composition is 100% solids.

[0017] In one embodiment, the non-adhesive material can be any materialthat can be used as the ink on a printing machine, provided that upondrying, cooling, and/or curing, the non-adhesive material is not tacky.The non-adhesive material may be made of organic polymeric material suchas polyurethane, polyvinyl chloride, acrylic polymers, acetate,polyethylene, polypropylene or polystyrene and the like.

[0018] In one embodiment, the non-adhesive composition is a UV curableink. The ultraviolet radiation curable inks useful in the inventiongenerally comprise a binder which comprises one or morephotopolymerizable monomers. The photopolymerizable monomers generallyare ethylenically unsaturated compounds. The unsaturated compounds maycontain one or more olefinic double bonds, and they may be low molecularweight compounds, (monomeric) or high molecular weight compounds(oligomeric). Illustrative examples of monomers containing one doublebond are acrylates such as alkyl(meth)acrylates orhydroxyalkyl(meth)acrylates such as methyl-, ethyl-, butyl-,2-ethylhexyl- or 2-hydroxyethylacrylate, isobornylacrylate, methyl- orethylmethacrylate. Further examples of photopolymerizable monomers areacrylonitrile, acrylamide, methacrylamide, N-substituted (meth)acrylamides, vinyl esters such as vinyl acetate, vinyl ethers such asisobutylvinyl ether, styrene, alkylstyrenes and halostyrenes,N-vinylpyrrolidone, vinyl chloride or vinylidene chloride.

[0019] Monomers containing a plurality of double bonds are typically thediacrylates of ethylene glycol, 1,3-propylene glycol, 1,4-butaneodiol,1,4-cyclohexane diol, neopentyl glycol, hexamethylene glycol, orbisphenol A polyacrylates such as trimethylolpropane triacrylate andpentaerythritol triacrylate or tetraacrylate, vinyl acrylate, divinylbenzene, divinyl succinate, diallyl phthalate, triallylphosphate,triallylisocyanurate or tris(2-acryloyloxy)ethyl-isocyanurate.

[0020] Typical examples of high molecular weight (oligomeric)polyunsaturated compounds are acrylated epoxy resins, acrylatedpolyethers, acrylated polyurethanes or acrylated polyesters. Furtherexamples of unsaturated oligomers are unsaturated polyester resins whichare normally prepared from maleic acid, phthalic acid and one or morediols and which have molecular weights of about 500 to about 3000. Suchunsaturated oligomers may also be referred to as prepolymers. Singlecomponent systems based on photocurable prepolymers are often used asbinders for printing inks. Unsaturated polyester resins are normallyused in two-component systems together with a monounsaturated monomersuch as described above, preferably with styrene.

[0021] The unsaturated compounds also can be used in admixture withnon-photopolymerisable film-forming components. These components maytypically be drying polymers or their solutions in organic solvents,such as nitrocellulose. They may also, however, be chemically curable orthermocurable resins such as polyisocyanates, polyepoxides or melamineresins. The concomitant use of thermocurable resins is important for usein so-called hybrid systems which are photopolymerised in a first stepand crosslinked by a thermal after treatment in a second step.

[0022] The UV radiation curable inks also should contain at least onephotoinitiator. A wide range of different photoinitiators is at presentavailable for UV radiation curable systems. They include benzophenoneand benzophenone derivatives, benzoin ethers, benzil ketals,dialkoxyacetophenones, hydroxyacetophenones, aminoacetophenones,haloacetophenones or acryloxyphosphine oxides. They differ in that theyhave different absorption maxima. To cover a wide absorption range it ispossible to use a mixture of two or more photoinitiators. The totalamount of photoinitiator in the UV radiation curable compositions may bein the range of from about 0.05 to about 7, or 10% by weight of thetotal composition. Preferably the compositions contain from about 0.2%to about 5% by weight of the photoinitiator.

[0023] Amines may be added to accelerate the photopolymerisation, forexample triethanolamine, N-methyl-diethanolamine,p-dimethylaminobenzoate or Michler's ketone. The photopolymerisation canfurther be accelerated by the addition of photosensitisers whichdisplace or broaden the spectral sensitivity. These photosensitisers arepreferably aromatic carbonyl compounds such as thioxanthone,anthraquinone and 3-acyl-coumarin derivatives as well as3-(aroylmethylene)-thiazolines.

[0024] Hindered amine light stabilizers (HALS) which function asco-stabilizers, also may be added to the UV radiation curable printingcompositions used in the present invention. Examples of hindered aminelight stabilizers include those listed and recited in U.S. Pat. Nos.5,112,890 and 4,636,408, which are incorporated herein by reference. Aspecific example of a hinder amine light stabilizer useful in theprinting inks is Tinuvin 292 which is identified asbis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate.

[0025] In addition to the above described binder materials andphotoinitiators, the UV radiation curable inks used in the presentinvention may also contain coloring matter selected from organicpigments, inorganic pigments, body pigments and dyes which are known andhave been used in this art. Examples of useful pigments include titaniumdioxide, cadmium yellow, cadmium red, cadmium maroon, black iron oxide,carbon black, chrome green, gold, silver, aluminum and copper. Examplesof dyes include alizarine red, Prussian blue, auramin naphthol,malachite green, etc. Generally the concentration of the pigment or dyein the ink will be from about 0 to about 70% by weight, and in oneembodiment, from about 0.1% to about 50% by weight.

[0026] In addition to the above described coloring matter, the UVradiation curable inks used in the present invention may also containfillers, extenders, surfactants, and the like which are known and havebeen used in this art. Examples of useful fillers and extenders includesilicon dioxide, fumed silica, glass or ceramic microspheres, and glassor ceramic bubbles. Generally the concentration of the filler orextender will be from about 0 to about 70% by weight, and in oneembodiment, from about 0.5% to about 50% by weight.

[0027] The printing inks may also contain at least one UV absorber whichprovides weathering protection and helps prevent microcracking. Theamount of UV absorber included in the UV radiation curable ink should bemaintained at a practical minimum since the presence of the UV absorbermay increase the curing rate. A variety of UV absorbers are known anduseful in the present invention and these include UV absorbers belongingto the group of photopolymerisable hydroxybenzophenones andphotopolymerisable benzotriazoles. U.S. Pat. No. 5,369,140 describes aclass of 2-hydroxyphenyl-s-triazines that are useful as UV absorbers forradiation curable systems. The triazines are effective for stabilizingcured films when exposed to sunlight over a long period of time, andthese stabilizers do not interfere with UV radiation curing of the inks.The triazine UV absorbers are effective in amounts of from about 0.1 toabout 2% by weight. The UV absorbers may be used in combination withother light stabilizers such as sterically hindered amines. Thedisclosure of the '140 patent is hereby incorporated by reference forits disclosure of such UV absorber combinations. U.S. Pat. Nos.5,559,163 and 5,162,390 also describe UV absorbers which are useful inthe inks of the present invention.

[0028] Examples of useful UV curable inks include those available fromDecochem under the trade designation Poly-Rad plastics, as well as UVcurable inks commercially available from Acheson and Dow ChemicalCompany.

[0029] In one embodiment of the invention, the ink used to form thenon-adhesive material on the adhesive layer is a coalescing ink. The inkdoes not efficiently wet out on the surface of the adhesive, butcoalesces into smaller areas of ink with an increase in height. Thus,depending on the degree of coalescence, a line of printed ink can form anarrower line, or a line made up of what appear to be random small beadsof ink, or a combination, all with an increase in height. The narrowerline, small beads, or combination are then embedded into the adhesive.The thickness of the ink applied to the surface of the adhesive layercan also affect the degree of coalescence. Surfactants may be added tothe ink composition to control the degree of coalescence as well.

[0030] In one embodiment of the invention, the ink used to form thenon-adhesive material comprises a porous non-adhesive. The porousnon-adhesive may have elastomeric properties, so that if it iscompressed, it essentially returns to its original shape. For examplethe porous non-adhesive comprises an ink containing a blowing agent thatcauses the ink to expand, forming an open or closed cell, or combinationthereof. The blowing agent is activated, for example, by the applicationof heat to the ink. Other examples of porous non-adhesives includesuspensions of gas and/or particles in a binder. The porous non-adhesiveis then embedded into the adhesive layer. The porous non-adhesive fillsthe depression created in the embedding step, resulting in a facestocklayer having a smooth outer appearance.

[0031] The non-adhesive material is generally present in a pattern. Thepattern can be a plurality of dots, lines, or any geometric figure, thatprovides a path for air egress from the adhesive article. When lines areused, at least about 50% of the pattern should extend to the edge of theadhesive article to obtain acceptable air egress. The lines and dots mayvary in size provided that air egress is maintained. The lines and otherpatterns generally have an average thickness from about 0.3μ to about100μ, or from about 0.5μ to about 50μ, or from about 2μ to about 20μ.The width of the lines may also vary widely. An example of a usefulrange for line width is from about 12μ to about 250μ, or from about 25μto about 125μ, or from about 50μ to about 75μ. The pattern may be a gridof intersecting lines, a weave pattern, a waffle pattern, diagonalstraight and curved lines, tiled geometric figures, such as hexagons,rectangles, overlapping circles or triangles, or lines in a cross hatchpattern. Combinations of patterns may be used such as a grid ofintersecting lines with random or patterned dots. The non-adhesivematerial may be applied by any means.

[0032] In one embodiment, the non-adhesive material is an ink comprisinga UV curable polymer composition, such as a UV curable acrylic orpolyurethane composition. After application, the ink is cured byirradiation in a UV exposure apparatus as is well known to those skilledin the art of printing and UV curing. UV light sources such as lowpressure mercury lamps, high pressure mercury lamps, xenon lamps, arclamps and gallium lamps are useful. It is also possible, but notnecessary, to improve the curability of the ink by heating afterirradiation.

[0033] In one embodiment, the non-adhesive material is a polymercomposition which is able to be printed by any suitable printingtechnique such as screen printing, roller coat printing, flexographicprinting, lithographic printing, gravure printing, laser printing, inkjet printing, brushing, spraying, dipping or coating. The type ofprinting may be any type which can print on the pressure sensitiveadhesive. One particularly useful printing method is a modification offlexographic printing which provides both the printing and embedding ofthe non-adhesive material.

[0034] In one embodiment, the non-adhesive layer is a printing inkhaving a thickness from about 0.3 to about 100 microns, from about 0.5to about 50 microns, or from about 2 to about 20 microns. Thenon-adhesive material may also be applied to the pressure sensitiveadhesive by means of patterned vacuum metallization or sputtering. Inthis embodiment, the non-adhesive layer typically has a thickness fromabout 30 to about 3000, from about 100 to about 2000, or from about 300to about 1500 nanometers.

[0035] As described above, the adhesive article has a facestock, anadhesive layer, a plurality of non-adhesive material and optionally theconstruction has a release liner. The facestock may be any of thosewhich are useful for decorative or graphic image applications. Thefacestocks typically have a thickness from about 10 to about 300, orfrom about 25 to about 125 microns. The facestocks include paper,polyolefins (linear or branched), polyamides, polystyrenes, nylon,polyesters, polyester copolymers, polyurethanes, polysulfones,polyvinylchloride, styrene-maleic anhydride copolymers,styrene-acrylonitrile copolymers, ionomers based on sodium or zinc saltsof ethylene methacrylic acid, polymethyl methacrylates, cellulosics,fluoroplastics, acrylic polymers and copolymers, polycarbonates,polyacrylonitriles, and ethylene-vinyl acetate copolymers. Included inthis group are acrylates such as ethylene methacrylic acid, ethylenemethyl acrylate, ethylene acrylic acid and ethylene ethyl acrylate.Also, included in this group are polymers and copolymers of olefinmonomers having, for example, 2 to about 12 carbon atoms, and in oneembodiment 2 to about 8 carbon atoms. These include the polymers ofalpha-olefins having from 2 to about 4 carbon atoms per molecule. Theseinclude polyethylene, polypropylene, poly-1-butene, etc. An example of acopolymer within the above definition is a copolymer of ethylene with1-butene having from about 1 to about 10 weight percent of the 1-butenecomonomer incorporated into the copolymer molecule. The polyethylenesthat are useful have various densities including low, medium and highdensity ranges. The low density range is from about 0.910 to about 0.925g/cm³; the medium density range is from about 0.925 to about 0.940g/cm³; and the high density range is from about 0.94 to about 0.965g/cm³. Films prepared from blends of copolymers or blends of copolymerswith homopolymers also are useful. The films may be extruded as amonolayer film or a multi-layered film.

[0036] In one embodiment, the first facestock is a polymeric facestock,which contains migratory additives. The facestocks are preferablypolyvinylchloride facestocks. The additives include plasticizers andantioxidants. The plasticizer is a high-boiling solvent or softeningagent, usually liquid. It is an ester made from an anhydride or acid anda suitable alcohol that usually has between 6 to 13 carbon atoms. Theplasticizers may be adipate, phosphate, benzoate or phthalate esters,polyalkylene oxides, sulfonamides, etc. The plasticizers include but arenot limited to DOA plasticizer (dioctyl adipate), TEG-EH plasticizer(triethylene glycol di-2-ethylhexanoate), TOTM plasticizer (trioctyltrimellitate), triacetin plasticizer (glyceryl triacetate), TXIBplasticizer (2,2,4-trimethyl-1,3-pentanediol diisobutyrate), DEPplasticizer (diethyl phthalate), DOTP plasticizer (dioctylterephthalate), DMP plasticizer (dimethyl phthalate), DOP plasticizer(dioctyl phthalate), DBP plasticizer (dibutyl phthalate), polyethyleneoxide, toluenesulfonamide,dipropylene glycol benzoate, and the like.

[0037] The adhesive articles have a continuous adhesive layer, typicallya pressure sensitive adhesive layer. In some applications, the adhesivemay be a heat activated adhesive, as distinguished from a pressuresensitive adhesive. The adhesive layer typically has a thickness fromabout 10 to about 125, or from about 25 to about 75, or from about 10 toabout 50 microns. In one embodiment, the coat weight of the pressuresensitive adhesive is in the range of about 10 to about 50 grams persquare meter (gsm), and in one embodiment about 20 to about 35 gsm. Thepressure-sensitive adhesive can be any pressure sensitive adhesive knownin the art. These include rubber based adhesives, acrylic adhesives,vinyl ether adhesives, silicone adhesives, and mixtures of two or morethereof. Included are the pressure sensitive adhesive materialsdescribed in “Adhesion and Bonding”, Encyclopedia of Polymer Science andEngineering, Vol. 1, pages 476-546, Interscience Publishers, 2nd Ed.1985, the disclosure of which is hereby incorporated by reference. Thepressure sensitive adhesive materials that are useful may contain as amajor constituent an adhesive polymer such as acrylic type polymers,block copolymers, natural, reclaimed or styrene butadiene rubbers,tackified natural or synthetic rubbers, random copolymers of ethyleneand vinyl acetate, ethylene-vinyl-acrylic terpolymers, polyisobutylene,poly(vinyl ether), etc. The pressure sensitive adhesive materials aretypically characterized by glass transition temperatures in the range ofabout −70° C. to about 10° C.

[0038] Other materials in addition to the foregoing resins may beincluded in the pressure sensitive adhesive materials. These includesolid tackifying resins, liquid tackifiers (often referred to asplasticizers), antioxidants, fillers, pigments, waxes, etc. The adhesivematerials may contain a blend of solid tackifying resins and liquidtackifying resins (or liquid plasticizers). Particularly usefuladhesives are described in U.S. Pat. No. 5,192,612 and 5,346,766 whichare incorporated herein by reference.

[0039] The pressure sensitive adhesive can be applied using standardcoating techniques, such as curtain coating, gravure coating, reversegravure coating, offset gravure coating, roller coating, brushing,knife-over roll coating, air knife coating metering rod coating, reverseroll coating, doctor knife coating, dipping, die coating, spraying, andthe like. The application of these coating techniques is well known inthe industry and can effectively be implemented by one skilled in theart. The knowledge and expertise of the manufacturing facility applyingthe coating determine the preferred method. Further information oncoating methods can be found in “Modern Coating and Drying Technology”,by Edward Cohen and Edgar Gutoff, VCH Publishers, Inc., 1992.

[0040] Release liners for use in the present invention may be thoseknown in the art. In general, useful release liners include polyethylenecoated papers with a commercial silicone release coating, polyethylenecoated polyethylene terephthalate films with a commercial siliconerelease coating, or cast polypropylene films that can be embossed with apattern or patterns while making such films, and thereafter coated witha commercial silicone release coating. A preferred release liner iskraft paper which has a coating of low density polyethylene on the frontside with a silicone release coating and a coating of high densitypolyethylene on the back side. Other release liners known in the art arealso suitable as long as they are selected for their releasecharacteristics relative to the pressure sensitive adhesive chosen foruse in the present invention. In one embodiment of the invention, therelease liner has a moldable layer of polymer under the release coating.The moldable layer is typically a polyolefin, such as polyethylene orpolypropylene. The surface of the release layer of the release liner mayhave a textured finish, a smooth finish, or a patterned finish. Therelease layer may have a randomly microstructured surface such as amatte finish, or have a pattern of three-dimensional microstructures.The microstructures may have a cross-section which is made up ofcircles, ovals, diamonds, squares, rectangles, triangles, polygons,lines or irregular shapes, when the cross-section is taken parallel tothe surface of the release surface.

[0041] In one embodiment, the release liner has a release coating onboth sides; one side having a release coating of a higher release valuethan the release coating of the other side.

[0042] In one embodiment, the adhesive layer of the articles has aSheffield roughness of at least about 10 or at least about 75, or atleast about 150. The adhesive layer may itself have the roughness or maybe formed when the adhesive is coated onto a release liner. It isunderstood that the release liner may have a Sheffield roughness atleast about 10 or at least about 50, or at least about 75 or at leastabout 150. The adhesive will replicate the complementary texture orpattern of the release liner. Alternatively, the release liner can bemuch rougher depending on the configuration of the adhesive article. TheSheffield roughness is determined by TAPPI T 538 om-88.

[0043] Applicant has discovered that the addition of the non-adhesivematerial either on or in the adhesive layer provides improved airegress. The non-adhesive may be embedded so that its outer surface iseven with the plane of the adhesive surface. Alternatively, thenon-adhesive may be embedded so that its outer surface extends beyondthe plane of the adhesive surface, or embedded so that its outer surfaceis below the plane of the adhesive surface (i.e., within the adhesivelayer). When the non-adhesive material is embedded to a level even withthe plane of the adhesive layer, the non-adhesive material provides airegress along the interface. This is particularly true for the smallerbubbles which form as the natural result of laying the adhesiveconstruction onto a substrate. Even when applied properly, small bubblesare still formed. The air in these bubbles needs a route to egress. Theinterface of the non-adhesive material and the substrate is the areawhere this occurs. When the non-adhesive material extends beyond theadhesive layer, the non-adhesive material provides repositionabilityand/or slideability as well as air egress. This is of particularadvantage when applying adhesive articles to surfaces that are aboveroom temperature. The amount of the non-adhesive material extendingbelow the adhesive layer needs to be only sufficient to prevent contactof the adhesive layer with the substrate.

[0044] The invention is further described by referring to the Figures.Referring to FIG. 1a, article 10 has facestock 11 in adhesive contactwith adhesive layer 12. Adhesive layer 12 has embedded within itnon-adhesive material 13. Embedding may be carried out using pressureand/or heated rollers or a platen, whereby the non-adhesive material ispressed into the adhesive layer. Alternatively, the non-adhesivematerial is embedded into the adhesive layer by winding the article sothat the patterned lower surface of the adhesive is in contact with thefront (upper) surface of the facestock. The facestock may have a releasecoating on its front surface. It is understood that at least a majoramount of the non-adhesive material is embedded within adhesive layer12. Typically more that 75%, and more than 85% of the thickness of thenon-adhesive material 13 is embedded in the adhesive layer 12.

[0045] In referring to FIG. 1b, the adhesive article 10 has theadditional element of a release liner 14. The release liner 14 is inreleasable adhesive contact with adhesive layer 12 and contactsnon-adhesive material 13. The adhesive layer 12 is also in adhesivecontact with facestock 11. Embedding the non-adhesive material into theadhesive layer may be carried out by applying the release liner to theadhesive layer. The pressure used in applying the release liner embedsthe non-adhesive into the adhesive layer.

[0046] In another embodiment, the adhesive article comprises a firstrelease liner in adhesive contact with an adhesive layer. The adhesivelayer has embedded into its exposed surface a pattern of non-adhesivematerial. A second release liner is applied to the patterned exposedadhesive surface. The surface of the second release liner in contactwith the adhesive layer may be textured. The texture may be a randomtexture or a patterned texture.

[0047] Referring to FIG. 2a, article 20 has facestock 21, which is inadhesive contact with adhesive layer 22. Adhesive layer 22 is inadhesive contact with non-adhesive material 23 embedded in adhesivelayer 22. Adhesive layer 22 has a textured surface 24. In FIG. 2b, thearticle has the additional element of a release liner 25. The releaseliner 25 is in adhesive contact with adhesive layer 22 and in contactwith the non-adhesive material 23 embedded in adhesive layer 22. Itshould be noted that the release liner in the present invention may betextured. The textured surface of the adhesive layer may be producedduring the embedding step. Alternatively, the texture in the releaseliner may be transferred to the adhesive layer during the adhesivecoating process. Commercially available textured liners may be used.

[0048] In another embodiment, illustrated in FIG. 3a, an adhesivearticle 30 having improved air egress is provided by simultaneouslyprinting and embedding a pattern of non-adhesive areas 33 into thesurface of an adhesive 32 on a release liner 34. Using flexographicprinting techniques, a pattern, such as diamonds, is printed into theexposed surface of an adhesive 32 on a release liner 34. Thenon-adhesive material 33 is a non-adhesive resin which upon drying,cooling, and/or curing maintains its shape. The printing techniqueembeds the print into the soft surface of the adhesive 32, leavingchannels 35 with most of the printing compound on the bottom of thechannels. Thus, the top surface of the printing compound 33 is below theplane of the upper surface of the adhesive layer 32. The non-adhesivematerial 33 is chosen from those materials that prevent the adhesivefrom flowing back into the channels 35 created by the printing process.Examples of such non-adhesive materials include hard PMMA, or a twocomponent urethane. Referring to FIG. 3b, the printed adhesive 32 withchannels 35 is transferred by lamination to a facestock 31, maintainingthe channels in the adhesive. Upon removal of the release liner 34 andapplication of the exposed adhesive to the surface of substrate 37 usingpressure the channels 35 collapse or partially collapse, forming voids36 at the interface between the adhesive 32 and the substrate 37,allowing trapped air to move to the exposed edges, as illustrated inFIG. 3c.

[0049] In one embodiment of the present invention, the adhesive articleis prepared by applying a non-adhesive material to the adhesive surfaceof an adhesive article. The non-adhesive material may be fully orpartially embedded into the adhesive surface. Embedding may be carriedout using pressure and/or heated rollers or a platen, whereby thenon-adhesive material is pressed into the adhesive surface. The rollermay be a silicone rubber roller. Embedding into the adhesive typicallyoccurs at a temperature from about 65° to about 200° F., or from about100° to about 150° F. The embedding pressure for embedding into theadhesive is typically between about 15 to about 100 psi, or from about25 to about 50 psi. Alternatively, the non-adhesive material may beembedded into the adhesive layer by applying with pressure anotherlayer, such as a release liner or facestock layer onto the non-adhesivepatterned surface of the adhesive layer. The non-adhesive material mayalso be embedded into the adhesive layer by winding up the adhesivelayer coated onto a facestock or release liner so that the non-adhesivematerial is embedded into the adhesive layer when the exposed surface ofthe adhesive contacts the outer surface of the facestock or releaseliner. The non-adhesive material will generally be embedded at a levelof at least about 50%, or at least about 75%, or at least about 85% ofthe thickness of the non-adhesive material, or embedded to a level equalto the surface of the embedding media.

[0050] In another embodiment of the present invention illustrated inFIGS. 4a-b, an adhesive article having improved air egress is providedby simultaneously printing and embedding a pattern of non-adhesive areasinto the surface of an adhesive on a facestock. The non-adhesive areasmay be printed and embedded by flexographic printing techniques. Thefacestock may be, for example, cast or extruded vinyl. The non-adhesivematerial is a non-adhesive resin which upon drying, cooling, and/orcuring maintains its shape. Referring to FIG. 4a, an article havingimproved air egress is provided by simultaneously printing and embeddinga pattern of non-adhesive areas 43 into the surface of an adhesive 42 ona facestock 41. The printing technique embeds the print into the softsurface of the adhesive 42, leaving channels 45 with most of theprinting compound on the bottom of the channels. The non-adhesivematerial is chosen from those materials that prevent the adhesive fromflowing back into the channels created by the printing process. Examplesof such non-adhesive materials include hard PMMA, or a two componenturethane. Referring to FIG. 4b, a release liner 44 is laminated to theexposed printed surface of the adhesive 42, maintaining the channel 45in the adhesive 42. Upon removal of the release liner 44 and applicationof the exposed adhesive to a surface using pressure, the channel 45collapses or partially collapses, allowing trapped air to move to theexposed edges.

[0051]FIGS. 5a-b illustrate another embodiment. An adhesive articlehaving improved air egress characteristics as well as improved facestocksmoothness is provided by simultaneously printing and embedding apattern of non-adhesive material into an adhesive on a facestock. Thenon-adhesive material pattern may be printed and embedded by usingflexographic printing techniques. The non-adhesive material issubsequently foamed to form a porous non-adhesive. The porousnon-adhesive partially, completely, or overly fills the channels in theadhesive. Referring to FIG. 5a, a pattern of non-adhesive material 53 isprinted into the exposed surface of an adhesive 52 on a facestock 51.The printing technique presses the non-adhesive material into the softsurface of the adhesive, leaving a pattern with most of the non-adhesivematerial on the bottom of the channel. The non-adhesive material 53 iscomprised of a resin which upon drying, cooling, and/or curing is foamedto partially, completely, or overly fill the channel forming a porousnon-adhesive. Referring to FIG. 5b, the adhesive with the porousnon-adhesive channels is transferred by lamination to a release liner54. Upon removal of the release liner and application of the exposedadhesive to a substrate surface with pressure, the porous non-adhesivein the channel collapses slightly, allowing trapped air to move to theexposed edges. Removal of the application pressure allows the porousnon-adhesive to return to its original uncompressed shape, removingtexture from the surface of the facestock.

[0052]FIGS. 6a-c illustrate another embodiment. An adhesive articlehaving improved air egress, characteristics as well as improvedfacestock smoothness is provided by simultaneously printing andembedding a pattern of non-adhesive material into an adhesive on arelease liner. The non-adhesive material pattern may be printed andembedded by using flexographic printing techniques. The non-adhesivematerial is subsequently foamed to form a porous non-adhesive. Theporous non-adhesive partially, completely, or overly fills the channelsin the adhesive. Referring to FIG. 6a, a pattern of non-adhesivematerial 63 is printed into the exposed surface of an adhesive 62 on arelease liner 64. The printing technique presses the non-adhesivematerial 63 into the soft surface of the adhesive 62, leaving a patternwith most of the non-adhesive material 63 on the bottom of the channel.The non-adhesive material 63 is comprised of a resin which upon drying,cooling, and/or curing is foamed to partially or completely fill thechannel. Referring to FIG. 6b, the printed adhesive with the porousnon-adhesive channels is transferred by lamination to a facestock 61.Referring to FIG. 6c, upon removal of the release liner 64 andapplication of the exposed adhesive 62 to a substrate surface 67 withpressure, the porous non-adhesive 63 in the channel collapses slightly,forming voids 65 at the interface between the adhesive 62 and thesubstrate 67, allowing trapped air to move to the exposed edges. Removalof the application pressure allows the foamed print to return to itsoriginal uncompressed shape, removing texture from the surface of thefacestock 61.

[0053] In another embodiment, a random pattern of non-adhesiveparticulates, such as for example, glass beads, can be applied to thesurface of the adhesive layer and then partially or fully embedded intothe adhesive layer. The non-adhesive particulate, in addition to glass,may be made of organic and inorganic particles, including but notlimited to polymers, ceramics and metals. The non-adhesive particulatemay be spherical, cubic, irregularly shaped, solid, porous, hollow,elastic or inelastic. Alternatively, the randomly distributednon-adhesive particulate material may be applied to and then partiallyor fully embedded into the release liner.

[0054] In another embodiment, non-adhesive material is applied to andembedded into the upper surface of the adhesive layer. The release lineralso has a pattern of non-adhesive material printed thereon. The printednon-adhesive material may be embedded into the surface of the releaseliner prior to applying the adhesive onto the release liner. Uponremoval of the release liner from the adhesive, the non-adhesivematerial is transferred to the adhesive layer.

[0055] In yet another embodiment, non-adhesive material is applied toand embedded into the upper or lower surface of the adhesive layer. Therelease liner has randomly distributed non-adhesive particulate materialapplied to its release surface. The particulate non-adhesive materialmay be embedded into the surface of the release liner prior to applyingthe adhesive onto the release liner. Upon removal of the release linerfrom the adhesive, the non-adhesive material is transferred to theadhesive layer.

[0056] Another embodiment of the method of making the adhesive articlesof the present invention includes the steps of: (a) applying a patternof a non-adhesive material onto an adhesive layer that has been coatedonto a release liner; (b) embedding the non-adhesive material into theadhesive layer; and (c) applying an additional release liner with ahigher or lower release to the adhesive layer. The embedding andapplying steps may be combined. The additional release liner may beomitted if the initial release liner has a release means on bothsurfaces. These embodiment are commonly known as transfer adhesives oradhesive sandwiches.

[0057] Another embodiment of the method of making the adhesive articlesof the present invention includes the steps of: (a) applying a patternof a non-adhesive material onto an adhesive layer that has been coatedonto the back surface of a facestock; (b) embedding the non-adhesivematerial into the adhesive layer; and (c) winding the material so thatthe adhesive is in adhesive contact with the front surface of thefacestock. The embedding and applying steps may be combined. A releasemeans may optionally be added to the front surface of the facestock.This embodiment is commonly known as a linerless adhesive tape.

[0058] Another embodiment of the method of making the adhesive articlesof the present invention includes the steps of: (a) applying a patternof a non-adhesive material onto each of the outer surfaces of twoadhesive layers that have been coated onto the front and back surfacesof a facestock; (b) embedding the non-adhesive material into theadhesive layers; and (c) applying a release liner with a releasesurfaces on each of its two sides to the outer surface of one of theadhesive layers and winding the material so that the outer surface ofthe second adhesive layer is in adhesive contact with the second surfaceof the release liner. The embedding and applying steps may be combined.This embodiment is commonly known as a double faced adhesive tape.

[0059] While the invention has been explained in relation to itspreferred embodiments, it is to be understood that various modificationsthereof will become apparent to those skilled in the art upon readingthe specification. The features of the various embodiments of theadhesive articles described herein may be combined into within anadhesive article. The various methods of manufacturing the adhesivearticles of the present invention described herein may also be combined.Therefore, it is to be understood that the invention disclosed herein isintended to cover such modifications as fall within the scope of theappended claims.

1. An adhesive article comprising: a facestock having a front surfaceand a back surface; a continuous layer of adhesive having an uppersurface and a lower surface and end edges, wherein the upper surface ofthe adhesive is adhered to the back surface of the facestock; and apattern of non-adhesive material forms that provide a path for airegress to an end edge, wherein the non-adhesive material forms areembedded into the upper surface of the adhesive layer, each of saidnon-adhesive material forms having a top surface, wherein the topsurfaces of the non-adhesive material forms are even with or below theplane of the upper surface of the adhesive layer.
 2. The adhesivearticle of claim 1 wherein the non-adhesive material forms have anaverage thickness of about 30 nanometers to about 100μ.
 3. The adhesivearticle of claim 1 wherein the non-adhesive material comprises a UVcurable ink.
 4. The adhesive article of claim 1 wherein the pattern ofnon-adhesive material forms is applied by vacuum metallization orsputtering.
 5. The adhesive article of claim 4 wherein the non-adhesivematerial forms have an average thickness of about 30 to about 3000nanometers.
 6. The adhesive article of claim 1 wherein the pattern ofnon-adhesive material forms comprises a plurality of dots, lines orcombinations thereof.
 7. The adhesive article of claim 6 wherein thelines of non-adhesive material have an average width of from about 12μto about 250μ and an average thickness of from about 30 nanometers toabout 100μ.
 8. The adhesive article of claim 6 wherein at least 50% ofthe lines intersect the end edges of the adhesive layer.
 9. The adhesivearticle of claim 6 wherein the plurality of lines forms a grid pattern.10. The adhesive article of claim 1 wherein the adhesive layer comprisesa pressure sensitive adhesive.
 11. The adhesive article of claim 1wherein the adhesive layer comprises a heat-activated adhesive.
 12. Theadhesive article of claim 1 wherein the non-adhesive material comprisesa porous non-adhesive material.
 13. The adhesive article of claim 12wherein the porous non-adhesive material comprises an elastomer.
 14. Theadhesive article of claim 1 wherein the article is wound so that thelower surface of the adhesive is in adhesive contact with the frontsurface of the facestock.
 15. The adhesive article of claim 14 whereinthe front surface of the facestock has a release surface.
 16. Theadhesive article of claim 1 further comprising a release liner having arelease surface, wherein said release surface is adhered to the lowersurface of the adhesive layer.
 17. The adhesive article of claim 16wherein the release surface of the release liner has a textured surface.18. The adhesive article of claim 17 wherein the release surface has arandom texture.
 19. The adhesive article of claim 17 wherein the releasesurface has a patterned finish.
 20. The adhesive article of claim 17wherein the lower surface of the adhesive layer has a textured surfacecorresponding to the textured surface of the release liner.
 21. Theadhesive article of claim 16 wherein the release surface of the releaseliner has randomly distributed non-adhesive particulate materialthereon.
 22. The adhesive article of claim 21 wherein the randomlydistributed non-adhesive particulate material is at least partiallyembedded into the release surface.
 23. The adhesive article of claim 16wherein the release surface of the release liner has a non-adhesivematerial printed thereon.
 24. The adhesive article of claim 23 whereinthe non-adhesive material printed on the release surface of the releaseliner is embedded into the release surface.
 25. The adhesive article ofclaim 1 further comprising a second adhesive layer having an upper andlower surface, said lower surface adhered to the front surface of thefacestock.
 26. The adhesive article of claim 25 wherein a pattern ofnon-adhesive material forms is embedded into the lower surface of thesecond adhesive layer, each of said non-adhesive material forms having abottom surface, wherein the bottom surfaces of the non-adhesive materialforms are even with or above the plane of the lower surface of thesecond adhesive layer.
 27. An adhesive article comprising: a releaseliner having a release surface and a back surface; a continuous layer ofadhesive having an upper surface and a lower surface and end edges,wherein the upper surface of the adhesive is adhered to the releasesurface of the release liner; and a pattern of non-adhesive materialforms embedded into the lower surface of the adhesive layer, each ofsaid non-adhesive material forms having a bottom surface, wherein thebottom surfaces of the non-adhesive material forms are even with, above,or below the plane of the lower surface of the adhesive layer.
 28. Theadhesive article of claim 27 wherein the non-adhesive material formshave an average thickness of about 30 nanometers to about 100μ.
 29. Theadhesive article of claim 27 wherein the pattern of non-adhesivematerial forms are applied by vacuum metallization or sputtering. 30.The adhesive article of claim 27 wherein the non-adhesive materialcomprises a UV curable ink.
 31. The adhesive article of claim 27 whereinthe pattern of non-adhesive material forms comprises a plurality ofdots, lines or combinations thereof.
 32. The adhesive article of claim31 wherein the lines of non-adhesive material have an average width offrom about 12μ to about 250μ and an average thickness of from about 30nanometers to about 100μ.
 33. The adhesive article of claim 31 whereinat least 50% of the lines intersect the end edges of the adhesive layer.34. The adhesive article of claim 31 wherein the plurality of linesforms a grid pattern.
 35. The adhesive article of claim 27 wherein theadhesive layer comprises a pressure sensitive adhesive.
 36. The adhesivearticle of claim 27 wherein the adhesive layer comprises aheat-activated adhesive.
 37. The adhesive article of claim 27 whereinthe non-adhesive material comprises a porous non-adhesive material. 38.The adhesive article of claim 37 wherein the porous non-adhesivematerial comprises an elastomer.
 39. The adhesive article of claim 27further comprising a second release liner having a release surface,wherein said release surface is applied to the lower surface of theadhesive layer.
 40. The adhesive article of claim 39 wherein the releasesurface of the second release liner has a textured surface.
 41. Theadhesive article of claim 40 wherein the release surface of the secondrelease liner has a random texture.
 42. The adhesive article of claim 40wherein the release surface of the second release liner has a patternedfinish.
 43. The adhesive article of claim 40 wherein the lower surfaceof the adhesive layer has a textured surface that is complementary tothe textured surface of the second release liner.
 44. The adhesivearticle of claim 27 wherein the back surface of the release liner has arelease coating thereon, the release coating having a higher releasevalue than that of the release surface.
 45. The adhesive article ofclaim 44 wherein the article is wound so that the patterned lowersurface of the adhesive is in adhesive contact with the back surface ofthe release liner.
 46. The adhesive article of claim 27 wherein therelease surface of the release liner has a non-adhesive material printedthereon.
 47. The adhesive article of claim 46 wherein the non-adhesivematerial printed on the release surface of the release liner is embeddedinto the release surface.
 48. The adhesive article of claim 27 whereinthe lower surface of the adhesive layer has randomly distributednon-adhesive particulate material embedded therein.
 49. An adhesivearticle comprising: a facestock having a front surface and a backsurface; a continuous layer of adhesive having an upper surface and alower surface and end edges, wherein the upper surface of the adhesiveis adhered to the back surface of the facestock; and a pattern ofnon-adhesive material forms embedded into the lower surface of theadhesive layer, each of said non-adhesive material forms having a bottomsurface, wherein the bottom surfaces of the non-adhesive material formsare even with or above the plane of the lower surface of the adhesivelayer; and wherein the pattern of non-adhesive material forms is appliedby vacuum metallization or sputtering.
 50. The adhesive article of claim49 wherein the non-adhesive material forms have an average thickness ofabout 30 to about 3000 nanometers.
 51. The adhesive article of claim 49wherein the pattern of non-adhesive material forms comprises a pluralityof dots, lines or combinations thereof.
 52. The adhesive article ofclaim 51 wherein the lines of non-adhesive material have an averagewidth of from about 12μ to about 250μ and an average thickness of fromabout 30 nanometers to about 3000 nanometers.
 53. The adhesive articleof claim 52 wherein at least 50% of the lines intersect the end edges ofthe adhesive layer.
 54. The adhesive article of claim 52 wherein aplurality of lines forms a grid pattern.
 55. The adhesive article ofclaim 49 wherein the adhesive layer comprises a pressure sensitiveadhesive.
 56. The adhesive article of claim 49 wherein the adhesivelayer comprises a heat-activated adhesive.
 57. The adhesive article ofclaim 49 wherein the article is wound so that the patterned lowersurface of the adhesive is in adhesive contact with the front surface ofthe facestock.
 58. The adhesive article of claim 57 wherein the frontsurface of the facestock has a release surface.
 59. The adhesive articleof claim 49 further comprising a release liner having a release surface,wherein said release surface is adhered to the lower surface of theadhesive layer.
 60. The adhesive article of claim 59 wherein the releasesurface of the release liner has a textured surface.
 61. The adhesivearticle of claim 60 wherein the release surface has a random texture.62. The adhesive article of claim 59 wherein the release surface has apatterned finish.
 63. The adhesive article of claim 59 wherein the lowersurface of the adhesive layer has a textured surface that iscomplementary to the textured surface of the release liner.
 64. Theadhesive article of claim 59 wherein the release surface of the releaseliner has randomly distributed non-adhesive particulate materialthereon.
 65. The adhesive article of claim 64 wherein the randomlydistributed non-adhesive particulate material is at least partiallyembedded into the release surface.
 66. The adhesive article of claim 59wherein the release surface of the release liner has a non-adhesivematerial printed thereon.
 67. The adhesive article of claim 66 whereinthe non-adhesive material printed on the release surface of the releaseliner is embedded into the release surface.
 68. The adhesive article ofclaim 49 further comprising a second adhesive layer having an upper andlower surface, wherein the lower surface of the second adhesive isadhered to the front surface of the facestock.
 69. The adhesive articleof claim 68 wherein a pattern of non-adhesive material forms is embeddedinto the upper surface of the second adhesive layer, each of saidnon-adhesive material forms having a top surface, wherein the topsurfaces of the non-adhesive material forms are even with or below theplane of the upper surface of the second adhesive layer.